Field Crop 2024, Vol.7, No.2, 105-115 http://cropscipublisher.com/index.php/fc 109 5.3 Thorough land preparation Crop rotation and diversification are effective strategies for managing weedy rice by disrupting the weed's life cycle. Rotating rice with non-host crops can reduce the weed seed bank and prevent the buildup of weedy rice populations. For example, integrating different rice establishment methods and rotating with other crops can help manage weedy rice more effectively (Chauhan, 2013; Zhang et al., 2021; Ceseski et al., 2022). Increasing the seeding rate and using row seeding can enhance crop competition against weedy rice. Higher seeding rates can lead to quicker canopy closure, which suppresses weed growth by reducing light availability to the weeds. Narrow row spacing has also been found to reduce weed biomass and improve rice yield (Dass et al., 2016; Ceseski et al., 2022). 5.4 Crop rotation and diversification Flooding is a traditional method used in rice cultivation to suppress weed growth, including weedy rice. Maintaining a water layer in the field can inhibit the germination and growth of many weed species. This practice is particularly effective in wet-seeded rice systems where standing water can be maintained during the early stages of crop growth (Chauhan, 2013; Dilipkumar et al., 2022). The use of allelopathic rice varieties, which release biochemicals that inhibit the growth of surrounding weeds, is an emerging strategy in weedy rice management. These varieties can provide a natural means of weed suppression, reducing the reliance on chemical herbicides and contributing to sustainable weed management practices (Dass et al., 2016; Ceseski et al., 2022). By integrating these cultural practices, rice farmers can effectively manage weedy rice, reduce herbicide use, and promote sustainable rice production. 6 Integrative Weed Management Approaches 6.1 Combining cultural practices with mechanical methods Integrating cultural practices with mechanical methods has shown significant promise in managing weed infestations in rice cultivation. Cultural practices such as the use of competitive rice cultivars, high seeding rates, and narrow row spacing can enhance the crop's ability to suppress weeds. For instance, increasing crop density and using competitive genotypes have been found to reduce weed biomass significantly (Figure 1) (Zhang et al., 2021; Tiwari et al., 2023). Mechanical methods, such as harrowing and the use of conoweeders, can further enhance weed control when combined with these cultural practices. Studies have demonstrated that combining high crop density with post-emergence harrowing can increase grain yield by 25% and reduce weed biomass by 71% compared to standard practices (Kong et al., 2008). Additionally, the use of mechanical weeding tools like conoweeders has been effective in reducing weed infestations when used in conjunction with cultural practices (Benaragama and Shirtliffe, 2013). 6.2 Combining cultural practices with chemical methods The integration of cultural practices with chemical methods can also be an effective strategy for managing weeds in rice cultivation. Cultural practices such as the use of allelopathic rice varieties, proper planting patterns, and optimal flooding depth can enhance the effectiveness of herbicides. For example, allelopathic rice varieties combined with low-dose herbicide applications have been shown to completely control weed emergence and growth without reducing grain yield (Shekhawat et al., 2020). Similarly, the use of competitive rice cultivars and high seeding rates can reduce the need for herbicides by up to 50% (Tiwari et al., 2023). In direct-seeded rice systems, the application of herbicides like bispyribac sodium followed by mechanical weeding has been found to be highly effective in controlling both grassy and broadleaved weeds, resulting in higher grain yields and economic returns (Benaragama and Shirtliffe, 2013). 6.3 Examples of successful integrative approaches Several successful integrative weed management approaches have been documented in rice cultivation. One notable example is the use of a combination of cultural, mechanical, and chemical methods in direct-seeded rice systems. In a study conducted in the Kymore Plateau and Satpura Hills, the integration of bispyribac sodium application with the use of a conoweeder significantly reduced weed infestations and increased grain yield and
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